This invention relates to optical switchers, and more specifically, to an optical matrix switcher for routing and distribution of optical signals from multiple input sources to multiple output devices. Matrix switchers for electrical signals are widely used in applications requiring signal routing and distribution from multiple input sources to multiple output devices. For example, a video presentation system may include several input sources, such as video cameras, VCRs, computers and the like, and several output devices, such as computer monitors, projectors, etc. A matrix switcher would be used to connect the input sources to output devices and distribute and manipulate signals between inputs and outputs in desired combinations. This is accomplished by way of switching means connected to inputs and outputs contained in a matrix switcher, which can be turned xe2x80x9conxe2x80x9d or xe2x80x9coffxe2x80x9d depending on the need.
Fiberoptic technology allows signal transmission through optical fibers, which presents advantages over electrical transmission methods by providing high bandwidth and electrical isolation. It is therefore desirable to provide an optical matrix switcher which would have the same ability of routing and distribution of optical signals from multiple input sources to multiple output devices as matrix switchers for electrical signals.
Prior art accomplishes switching of optical signals by way of optical aligning, in some fashion, input and output optical fibers. For example, Lee (U.S. Pat. No. 4,834,488) aligns two fixed input optical fibers with two movable output optical fibers which are capable of changing positions. Aoyama (U.S. Pat. No. 4,239,331) employs a transparent dielectric plate capable of moving between switching positions, which provides optical connection between the input and output optical fibers. Minowa (U.S. Pat. No. 4,322,126) uses dielectric light-transmitting members movable by an electrically-controlled mechanism to provide optical connection between the input and output optical fibers. Winzer (U.S. Pat. No. 4,452,507) uses electromagnetic forces to move two movable fibers between two stoppers, thus providing optical connection with fixed fibers. Antell (U.S. Pat. No. 4,220,396) accomplishes optical connection between two pairs of movable fibers by moving them in two perpendicular directions. Hodge (U.S. Pat. No. 2,229,068) rotates a cylindrical member with respect to another cylindrical member in order to switch optical connections between the fibers in the cylindrical members. There are numerous other examples of how prior art accomplishes switching of optical signals, all of which involve optical alignment of input and output fibers by some mechanical means.
This invention is directed to an optical matrix switcher which does not use mechanical means of optical alignment of input and output fibers in order to accomplish switching. Rather, it comprises a number of input assemblies, each comprising a first input means optically connected to an input of an input beam shaping means and a first output means optically connected to an output of the input beam shaping means. The first input means can be a fiber conducting light and the first output means can be a lens. The input beam shaping means comprises a number of lenses having specific optical properties and disposed inside the input beam shaping means in a way that a beam of light irradiating the first input means will pass between the input and the output of the input beam shaping means and come out of the first output means shaped and compressed into a plane (xe2x80x9cshaped beamsxe2x80x9d).
As a result, when a beam irradiates one of the first input means, the shaped beam coming out of the first output means disposed on the input beam shaping means to which the first input means is connected, carries the same information as the beam irradiating the first input means.
An output assembly is substantially a mirror image of the input assembly. It comprises a number of beam shaping means, each having a second input means optically connected to the input of the beam shaping means, as well as a second output means optically connected to the output of the beam shaping means. The second input means can be a lens and the second output means can be a fiber conducting light.
A screen with a number of switching means is disposed between the first output means in the input assemblies and the second input means in the output assemblies. The switching means can be placed in an xe2x80x9conxe2x80x9d and xe2x80x9coffxe2x80x9d positions. In the xe2x80x9conxe2x80x9d position, switching means create an opening in the screen permitting light to pass through the screen. In the xe2x80x9coffxe2x80x9d position, switching means close the screen and prevent light from passing through the screen.
Each opening in the screen created by the switching means in the xe2x80x9conxe2x80x9d position is in an optical alignment with one of the first output means and one of the second input means, so that each of the first output means can be placed in an optical connection with any of the second input means by way of placing the corresponding switching means in the xe2x80x9conxe2x80x9d position. Accordingly, a signal (light) from any of the first input means can be sent to any of the second output means via the corresponding switching means in the xe2x80x9conxe2x80x9d position.
The advantages of this invention will be better understood with the reference to the following drawing figures and description of the preferred embodiments of this invention. The same numerals indicate the same elements in all drawing figures. The same letters indicates the same points in all drawing figures.